Disaster

A sudden, unplanned, calamitous event causing great damage or loss which results in the inability of an organization to provide critical business functions for some predetermined minimum period of time. (MS 1970)

A sudden, unplanned calamitous event, usually causing great damage or loss, making an organization unable to provide critical business functions for some predetermined minimum period of time. (SS540:2008)

A sudden, unplanned calamitous event causing great damage or loss. 1) Any event that creates an inability on an organisations part to provide critical business functions for some predetermined period of time. 2) In the business environment, any event that creates an inability on an organisation’s part to provide the critical business functions for some predetermined period of time. 3) The period when company management decides to divert from normal production response and exercises its disaster recovery plan. Typically signifies the beginning of a move from a primary to an alternate location.
Similar Terms: Business Interruption, Outage, Catastrophe. (DRII)

An unanticipated incident or event, including natural catastrophes, technological accidents, or human-created events, causing widespread destruction, loss, or distress to an organization that may result in significant property damage, multiple injuries, or deaths. (ASIS)